Is mysql 5.7 is old ? for rails?

Question

I have two questions:

• is MySQL 5.7 is old?
• what the best version of mysql for Rails 5.2?

Thanks!

Answer 1

1. No, it is not the latest, but is still supported (up to October 2020, extended support up to October 2023)
2. best is the one that's compatible and satisfies your requirements (and is supported)

Obviously you'd start new apps with most current one, but unless you desperately need some new feature - do not rush the upgrade.

Prior to upgrading - make sure you're not using any deprecated features (official manual is your friend - https://dev.mysql.com/doc/refman/8.0/en/upgrading.html ), have a good tests coverage, performance and error monitoring. Also have your team available during the upgrade, so that you'll have someone to help if something unexpected happens (like an error that did not show up in tests).

Upgrade options:

1. With a downtime - just make a backup, schedule downtime during usual lowest load time, bring your app down and upgrade server inplace (may take long for large databases, thus not for everyone)
2. With (hopefully) much less downtime - mysql supports replication to next version (5.7 -> 8.0 in this case) given both servers are GA-releases. You can create a 8.0 slave and make it the master once it is fully in sync. This way you only need to stop database writes during switching servers (heavily depends on your app, but a few minutes of downtime is still an option).